Branch-and-bound for the Precedence Constrained Generalized Traveling Salesman Problem

R. Salman, F. Ekstedt, P. Damaschke. Operations Research Letters, Vol. 48, Issue 2, Pages 163-166. March 2020.

Abstract

The Precedence Constrained Generalized Traveling Salesman Problem (PCGTSP) combines the Generalized Traveling Salesman Problem (GTSP) and the Sequential Ordering Problem (SOP). We present a novel branching technique for the GTSP which enables the extension of a powerful pruning technique. This is combined with some modifications of known bounding methods for related problems. The algorithm manages to solve problem instances with 12–26 groups within a minute, and instances with around 50 groups which are denser with precedence constraints within 24 h.

 




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